Sewing machine



Feb.26,194e. E POUMAC '2,395,579

SEWING MACHINE Filed Oct. 5l, 1942 4 Sheets-Sheet 2 l Feb. 26, 1946.

E. PoLlMAc SEWING MACHINE Filed Ost.y 51, 1942 4 SheetsrSheet 3 Feb. 26,1946. E. PoLlMAc I 2,395,579

SEWING MACHINE Filed Oct. 3l, 1942 l 4 Sheets-Sheet 4 Y Patented Feb. 26, 1946 OFFICE.v

SEWING CHENE Emeric Polimac, Chicago, lll., assigner to George I. Goldwyn and Herman Goldw'yn, Chicago, Ill., copartners doing business as Goldwyn Brothers Application October 31, 1942, Serial No. 464,050

(Cl. i12-162) 6 Claims.

This invention relates to improvements in sewing machines and it consists of the matters hereinafter described and more particularly pointed out in the appended claims.

The invention is especially concerned with power sewing machines for industrial use in forming an overcast or overedge stitch through cooperation between the needle and the looper and the loop spreader in the manner well known.v A machine of this kind is well adapted for sewing inV connection with relatively heavy material.

One of the objects of the present invention is to provide a sewing machine of the kind mentioned, which may be run at high speed and yet be economical in the use of power.

Another object of the invention is to provide a sewing machine of this kind which is devoid of gears and is quiet and vibrationless in operation.

A further object `of the invention is to provide a sewing machine of this kind that includes a folder which may be disposed closer to the needle so that the material operatedon is held in a better folded condition when presented to the needle and coacting stitch forming mechanism.

Also, it is an object of the invention to provide a sewing machine Ythat includesparts so .arranged as to cut a strip from the material operated upon and then fold inland overcast the margin left by the removal of the strip to provide a bound seam for the material The above mentioned objects of the invention, as well as others, together with the advantages thereof will more fully appear as the specification f proceeds.

, chine as taken on the line 4 4 of Fig. 3.

Fig. 5 is another longitudinal horizontal sectional view through a lower part of the sewing machine as taken on the line 5--5 of Fig. 3.

Fig. 6 is a detail transverse vertical sectional view through a part of the machine on the line -8-5 of Fi'g. 3 and will be more fully referred to later.

Fig. 'I is a detail perspective view of a shaft and arm assembly embodied in the sewing machine and which will be more fully referred to later.

Fig. 8 is a detail perspective view of parts of the machine associated with the folder mechanism thereof and which will hereinafter be referred to.

Fig. 9 is a fragmentary detail view on an enlarged scale of parts shown in Fig. 5 and more clearly shows the path of movement of the end of the loop spreader as will be mentioned in more detail later.

Referring now in detail to that embodiment of the invention illustrated in the drawings, the improved sewing machinel includes a hollow and generally upright casing or frame I0 divided into a lower part II and an upper part I2, as best appears in Fig. 3. At the left hand end of the casing, in substantially the horizontal plane of the junction between said upper and lower parts is a throat plate I3. The left hand portion Iof the upper casing part I2 is made as an extension which defines a recess I5 therebelow and which overhangs a part of the throat plate I3.

In the throat plate I 3 is a needle opening It (see Fig. 5). A vertically reciprocable needle bar il h-as guided bearing in the extension I4 andthe bottom end of said bar below said extension carries a clamp I8 for securing a needle I9. This needle is so disposed with respect to the needle opening i6 as to enter and leave the same in the reciprocation of the bar.

26 indicates the maindrve shaft of the sewing machine which is disposed longitudinally of the lower part II of the casing. The right hand end of said shaftI is journalled in and projects through the associated end wall 2| of the casing part II so that it may have a pulley or the like (not shown) attached thereto and driven from a suitable source of power. The left hand end of said shaft is journalled in and projects through the associated end wall 22 of the casing part II and there has'an eccentric 23 (see Fig. 2) fixed thereto and the function of which will appear later. Rising from the bottom of the casing part II is a boss 24 in which an intermediate part of the main drive shaft 20 also has bearing, thus providing a three point bearing for said shaft. The front part 25 of the wall 22 is offset inwardly and joins the rear part by means of a partition or bearing wall 26 and-this arrangement of walls forms a recess 2l which opens into or communicates at its top end with the recess I5 in the upper portion I2 of the casing. n

The shaft 2i) is provided toward its right hand end between the wall 2i and boss 24 with a counterbalanced crank 23 and between the boss 24 and Wall 22, said shaft is provided with a plurality of eccentrics 29-38 and 3l respectively.

In the upper casing part 2, about midway between its right and left hand ends is a stud 32 upon which is mounted a rocking lever 33 having oppositely disposed .arms 34 and .35 respectively that extend -toward said ends of said casingpart. The arm 34 is connected by a link 36 to a lateral extension 31 on that part of the needle bar between the top and bottom walls of the extension I4. The arm 35 of the lever 33 is operatively engaged with the top end of :a connecting rod 33,

the bottom end of which fisfoperatively engaged with the crank 28. Thus 'in the rotation Kof the shaft 25, the rod 38, lever 33 and link 36 impart a vertical reciprocation to the needle bar.

In the throat plate and disposed in planes on ,opposite `sides of theneedleareslots .40m which the rfeed .plates v4 l-L4l are disposed. 'Iihesepla'tes are carried upon the upper portion of 'the front :end .of a .member -42 ,disposed lbelow the throat plate as shown in Fig. 2. The lower portion yof saidfrontend of thememberisibifurcated asat 43 to receive the eccentric 23 on the main shaft 20.. The rear end 4of .the .member 42 is .disposed .betweenand 'is pivoted as at 4.4 to apair .of uprightarms 45 thatarexed to that end of a rock 4shaft .46 that .extends 'through the wall 22 before mentioned.

The shaft 46 is `arranged parallel to .but is spaced rearwardly ,from `the main drive shaft 2li.

The .other end .of the rock shaft '46 is suitablyV V ioturnalled in a part Vof jthe `boss '24. It is pro- .vided in .the plane of '.the eccentric .31 with adepending .arm 4.1 and said ,arm .is operatively engagedby .one .end of .a connecting rod 48. AThe .other end of .said rod .carries a strap 4.9 engaged with .the .eccentric 3|.

In the rotation .of vthe main shaft, the shaft 46 is rocked through `the eccentric 3L strap 49, rod 48 and varm 141 and 'through the arm '45 imparts a forwardly .and rearwardly reciprocating movement to the member 42,. 'TI'hrough the eccentric V23 .before mentioned, the Afeed plate end of the member '42 is raisedandlowered and this, incon- .nection with the reciprocating movement of the member 42,1'mparts proper feeding movement to the YAfeed dogs-4 l-4 I.

Associated with each feed dQg is a presser Hfoot .5.0 carried by the forward end .of an associated supporting .arm L51. The arms l-5l are pivoted at their rear end .as at '52. Each xarm 5I has a tension .element 53 associated therewith. The rear end .of ueach tension .element is mounted on va stud l,54 while the front end thereof bears against the top `end of ,an upright extension `55 on the front end of 'theassociated arm 51. A screw 55 (only ,oneof which -appearsinig. 2) is arranged to engage the .midportion .offthe associated tension `element whereby the tension of said Aelements .and the downward thrust or `pressure of eachpresserfoot 5B may be controlled.

Of course the presser feet must be `raised or lifted 'to 'permit .the passage or entrance of the material .operated upon, into position between the feed A plates ,or .dogs 14| and the presser feet. Therefore, the bottom end of a lift bar 5'! is engaged with .the mid ,portion of 'both arms 51 and .the Lopend ofthe lift bar is connected to one end of aleveri .that is Cpivoted as at 59 to 4a stud extending from the -rear of 'thellpper portion of the casing. Aspring 60 is so operatively .connected to this arm as 'to depress that end thereof connected to the lift bar. The lever 58 is so connected to a suitable treadle (not shown) that when the treadle is depressed, the presser feet 50--59 are elevated into a position above the feed dogs or plates so that the material operated upon may be entered into position upon the throat plate between the feed plates and presser feet. .After said material has -,been .so entered, the treadle before mentioned Vis released and the presser feet move into operative position with :respect to the feed dogs or plates and throat plate.

'60 'indicates a looper hook carried by an arm `fr!disposed 'in the l.recess 27. This arm is xed 'to the-liront end/of a rock shaft 62 just forwardly of Ethe wall '2S and in which a front end portion of the :shaft is .journalled The rear end of said shaft is journalled in the rear wall of the lower portion of the casing. Associated with the arm 6l and disposedjust forwardly thereof is a guard or deflector '63 .of a cam shape formation. This guard or deflector Yrocks with the .looper V60 and arm 'B1 vand 'is so arranged V.with respect Vthereto as to .be .engaged bythe `needle in `its movement `so 'that 'the same is `deflected out of lthe way of the point of the loo-perhook as the same swings upwardly toward 'the needle. Thus it'is assured that the needle can ,at no time be struck and bent out of shape by the 'loopen The shaft 62 .extends in a front `to rear direction ofthe casing and toward its Urear end itis vprovided with an upright .arm 64, the purpose of which'will soon appear. 'I'his `arm best appears in dotted lines in Fig. 3.

.B5 indicates a rock shaft thatisjournalled in the part of ,the boss 24 disposed in the upper .portion i2 .of the casing. Front *and rear arms ES-'G'l Aare xed 'to this rock .shaft and function as a bell oran'kflever.

The rear varm '61 is Aconnected `by a rod -68 -to the arm .Mon the rock shaft 62. The'front-a-rm 6.6 is operatively VVengaged with the upper end of a connecting rod SSLthe lower :end of'which carries a strap 1'0 that 'is operatively Vvengaged with 1 `the .eccentric 29. 1t Vapparent that `through the parts just .above described Athe vshaft t2 land its looper arm '6| and hook 60 lare rocked from-the main .shaft as 'thelatter is being Ydriven in one direction.

.1l indicates the loop 'spreader which f'is disposed substantially entirely -abovefthe lower portion I l of the casing and substantially entirely within the recess 15 in `the -upper portion 'I2 of the casing. This spreader is secured in the "bottom end of a spreader arm 12, the ftop lend of which is fixed to that end of 'a rock shaft 13 which extends into 'said recess 15 from gthe inside of said upper portion l2 of the casing. The axis ofthe shaft 13,;whicl'iis disposed in a 'horizontal plane, is arranged diagonally Yand not at a right angle `to the axis of the Ymain shaft '20. The rear end of said shaft is closer to a front to rear plane passing through the vneedle axis 'than is the front end of the shaft, as is Yobvious from Figsf3 and 4. An arm 14 is fixed to the Arear end of saidgshaft within lthe casing part f2 and this armis operatively engaged by the upper end of a connecting rod 1AT5, the'lowerend of which carries I a strap 1B 'that is vengaged on fthe eccentric 30. The assembly fas constituted by the shaft 13 and arms i12-14 best appearsin Fig. "1.

:It is `apparent that through the parts :lust described, 'the iooper and the loop spreader receive .a rocking movement from the main drive fsha'ft and this movement is :in timed vrelation 'with respect to the needle so that they coact therewith in forming overcast stitches.

With the shaft 'I3 arranged at the angle before mentioned, the point or hook of the loop spreader s 'll swings from a position to the rear and to the right hand side of the needle axis, to a position to the front and to the left hand side of said needle axis, as best appears in Fig. 9. This path of movement of said point of the loop spreader occurs when said point is in the bottom portion of its arc of swing and not in or toward the top portion of its arc of swing as in conventional overcast sewing machines.

In the drawings, the thread used in the sewing machine has been omitted for the purpose of clarity, it being understood that the parts are threaded substantially in the same manner as in a conventional sewing machine of this type.

On the right hand portion of the throat plate |3, in advance of the axial plane of the needle, is provided an upstanding block-like part 88 which forms the fixed part of a folder mechanism, the movable part of which is formed by a block-like foot 8| that is supported from above the throat plate, as will soon appear, The parts 80 and 8| coact to form a horizontal folder opening 82 (see Figs. 1 and 8) which extends from the front toward the rear of the throat plate. The -axis of this opening is disposed-adjacent but to the right hand side of the axis of the needle I9 and a part of this opening communicates with or is intersected by the needle opening I8 as appears in Fig. 5.

The folder part 8| is carried by the bottom end of an upright stem 83 which has sliding guided bearing in top and bottom ears 84 on a front or cover plate 85 for the upper portion |2 of the casing. A collar 8B is fixed to said stem between said ears and an expansion spring 81 surrounds that part of the stem between the top ear 8e and said collar. Said spring normally urges the stem downwardly so as to keep the folder block part 8| in a pressed down relation with respect to the throat plate and in operative relation with respect to the block part 8|).

To elevate the block-like folder part 8l so that the material operated upon may be introduced thereunder to the feed dogs and presser feet before mentioned, I provide the following structure.

9| indicates a stud that projects forwardly from the cover plate 85, A lever 92 is pivoted on said stud and which lever comprises oppositely extending arms 93 and 9e respectively. The free end of the lever arm 93 extends toward the stem 83 and under a collar 95 fixed to said stem. The arm 94 of said lever projects laterally beyond the right hand side of the casing as a whole so as to be connected up to a foot treadle (not shown) for operation. A spring 96 is xed at one end to the arm 94 and at its other end to a stud projecting forwardly from the front plate and this spring normally acts to swing the lever 92 counterclockwise. Thus, when the lever 92 is rocked clockwise by the treadle, before mentioned, the arm 93 by reason of its engagement with the collar 95 will raise the stem against the action of the spring 81 and lift the folder block part 8| upwardly from the throat plate to permit the passage of the material operated upon under said part 8|. As soon as the treadle has been released, the spring 96 causes the lever to swing oounterclockwise and until stopped by the engagement of the end of the arm 93 with the bottom ear 94 on the front plate. In this movement of the lever, the spring 8l, which was previously compressed, will expand and through the collar 86 will urge the stem downwardly so that the block-like part 8| again comes into a position wherein it coacts with the block part 80 in forming the folder.

With the folder block parts 89 and 8| arranged as described, the margin of the material operated upon, as it enters the folder opening 82, is curled or turned back upon itself as a substantially tight roll or fold and due to the position of said block-like parts with respect to the needle, said roll or seam is held quite tightly in its rolled condition and cannot unroll or expand before the overcast stitching has been formed thereabout to provide a good tight rolled or folded seam.

The machine thus far mentioned has a special advantage when used in reconditioning used burlap or other bags. In some instances it may be desired to remove or trim the old seam from a bag due to its worn condition and provide a good straight edge for the bag body so that the margin of the bag body along said edge is even and smooth and can be folded or rolled to provide a new side and bottom seam for the bag.

Therefore, when a trimmer is to be used in connection with the before mentioned construction, I provide the following: At the front of .the bottom portion of the casing, I provide a hollow housing that includes a top wall 98 and a front wall 99. The top wall has its top surface disposed somewhat below the top surface of the throat plate. Therefore, so that no obstruction is presented to the feed of the material operated upon as it passes from the top wall 98 to the throat plate and into the folder opening, I provide the ramp |88 best shown in Figs 2 and 8;

In the top wall I provide a slit |ll|, which extends in a forwardly and rearwardly direction and which is located in a plane spaced in a right hand direction from the axis ofthe folder opening 82.

A thin rotary trimmer blade or disc |82 has its bottom portion extending through this slit so that the rotating edge thereof coacts with said slit in trimming a margin of the bags fed thereto. This blade or disc is fixed to o-ne end of a horizontal shaft |83 that is journalled in brackets |84 projecting forwardly from the front or cover plate 85. This shaft may be driven in any suitable manner and preferably as it runs at high speed, it may be provided with its own driving motor.

On each side of the blade or disc I provide the guard plates |95 andY |95 respectively. These are so formed and so placed with respect to the disc that the operator feeding a bag to the machine cannot engage the blade with the fingers. The guard plate |86 is made as a part of a cover i8? for the shaft |83. The front bottom portion of the plate is cut away as at |98 and this forms a tongue |89, the free end edge of which substantially engages the associated side of the blade or disc. The rear bottoin'part of the plate-is bent laterally toward the folder block part 8|). Thus. when a bag'is presented to the machine in the operation thereof, the blade or disc trims off a strip leaving a nice clean edge for the bag margin. As this margin is fed toward the folder, it receives a slight upward turn as it leaves the tongue and follows the faceof the guard plate and is directed thereby into the folder opening B2, where it rolled or folded over and vthen overcast, as is obvious. The guard plate may be provided et the top with'a recess ||||l (see Fig. 2) whereby sharpening .means may he engaged with thereri-phery :of the rdisc for f.blade vto sharpen the same.

With the :loop l'spreader arranged 'to swing, as before mentioned, itispossiole -to locate :the cutting disc closer tothe lfolder :mechanism `so that it is not necessary for the operator to hand lreed the material yso iar before presenting 'it rto the folder mechanism and ftherefore the machine 'operatesmore efficiently. Also, lthis `arrangement permits :the use'of a larger-.diameter disc to give proper peripheral :speed in cutting.

The structure described is 'devoid `of gearing of any kind. Therefore, the `.structure is not onli7 :more economical to .produce but itcan `he run at higher speeds and withless vihrationand noise.

The :lower part of the ycasing .is oil tight and may contain .a quantity fof oil which many of the parts run submerged. ns to those par-.ts in the upper vcasi-ng part, ift ispointed out that the machine :containsagpressure oiling system therey fonbutas this system `forms .no part of the present `invention, it .is not Vnecessary 'to show or descrtbethe same.

The machine is especially useful .in trimming usedburlapbagscand then reseaming them infone operation.

While 'm describing the invention I `*have re- ;ferred in detail to the form zand arrangement Aoi the parte involved, the same is to be `considered only in the illustrative sense so thatl do not wish to be A'limited thereto vexcept as may be specifically .set vfor-th 'm the appended claims.

' .I-claim:

1. In a sewing machine, Vthe combina-tion of a casing, sa throat plate :supported thereby, a needle -bar mounted `for reciprocating movement toward and away from the throat plate, a rockalole :looper and .a vrockalo'le 'loop spreader arranged to cooperate with the .needle imforming rovercast stitching, meazns associated with .the throatplate and providing .a folder vmechanism vwith a material folding passage therethrough and having its inlet lenoldisposed in advance of :the needle, a material :support disposed iin advance of said throat plate, .a :high speed rotatablelcutting disc :arrangedzpa'r- 'allel with 'the Idirection of the feed of the material -to said ifolder means and coacting with a -part of said support for trimming the material operated `upon zasit is fed over-said support to the -folding means, :and a-guard plate -for one side of said cut- .ting :disc `having "a part vto the rear of the-disc .for `iImJa-rting Aa turning motion -to a marginal part of the material operated upon and for directing the same into :said folder mechanism.

2. In a sewing machine, :the combination of a hollow casing, la throat plate arranged outside of the casing, a main drive shaft ionmalled in the casing., fa needle carrying `bar '.-mounted .for reciprocating movement toward and away from said throat plate, :a rockable looper and Va rockable-loop spreader arranged outside of the .casing for cooperating with the needle in forming stitchesgsaid casing :having aa'ecess extending inwardly from one side thereof above said throat plate in 'which said loop spreader yis operatively disposed, rockshafts tovvhich-saidlooper and loop spreader 'respectively yare directly attached for movement, `said rock .shatts being horizontally disposed with their axes atsan angle to `each other and to the kaxis of the main shaft, said loop spreader having a point which .in the rocking movement of said spreader swings upwardlyfrom the bottom of .an .arc from .a position -to .the rear and to `one 4side of the needle .axis to va position to the front tand fto the other side .of the needle axis and then returns to the first position, and

means actuated from said ma-inshaft operatively connected within the casing to said rock shafts -to rock the latter.

:3. In a sewing machine, the combination of v`a casing having upper and lower parts, a throat plate on said lower casing part, a generally upright needle carrying bar mounted in said .upper casing part for reciprocating movement toward and :away from said throat plate, a main drive shaft journalled in the lower-casing part, a looper rock shaft journalled-in said lower casing part below the throat plate, a loop spreader .rockshaft journalled in the upper casing part `above said -throatlplata said lower casing part haningafbearing wallapproxmately parallel to said main drive shaft, said looper rock Ashaft being journalled in said bearing wall below the throat plate, said -rock shafts having their axes crossing the axis of the .main drive shaft, said upper casing parthavnga recess extending inwardly from one sidesaid rock shafts being disposed to the same side of the plane of the .needle and each having a part extending outside the associated casing part, -a louper and a loop spreader respectively each xed to Aone of said parts of the looper rock shaft and loop spreader rock shaft respectively extending outside of vsaid casing parts for cooperating with the needle in forming stitches, said loop spreader being disposed and operable in .said recess, and

means interiorly of said casing parts and -actu. rated from said main drive shaft operatively connected for rocking said looperand loop spreader rock shafts respectively.

4. In .a vsewing machine,` the combination `ofa casing having upper and lower parts, a throat .plate on said lower casing part, a-generally upright needle carrying bar mounted .in .said upper casing part for reciprocating movement toward Yand away from said throat-plate, a main .drive shaft journalled in the lower casing part, -.a looper rock shaft journalled in said lower casing .part below the throat plate with its axis crossing the axis Iof the main drive shaft, a loop spreader rock shaft jourhalled in the upper casing part above said throat plate with its axis crossing the axis of the :ma-in drive-shaft, said rock .shafts being disposed to the same side of the plane .of the .needle and each having a part extending outside the associated casing part, a looper and aloop spreader respectively each xed to one :of said parts of the looper rock shaft and loop spreader rock .shaft respectively extending .outside of .said

casing parts, for cooperating with the needle .in forming stitches, a bell crank, means on one of said parts journalling said bell-crank within the casing on an axis above the junction line of the casing having upper .and lower parts, a throat plate on said lower casing part, a generally up-v right .needle carry-ing har mounted in said upper casing part for reciprocating movement toward and Yaway from said throat plate, a. main drive .shaft journalled .in the .lower casing part, alooper rock shaft journalled vin said lower casing part below .the .throat plate with its axis crossing the axis ofthe main drive shaft, `a 'loop spreader rock shaft journalled in the upper casing part above said throat plate with its axis crossing the axis of the main drive-shaft, said rock shafts being disposed to the same side of the plane of the needle and each having a part extending outside the associated casing part, a looper and a loop spreader respectively each xed to one of said parts of the looper rock shaft and loop spreader rock shaft respectively extending outside of said casing parts, for cooperating with the needle in forming stitches, eccentrics on said main shaft, a strap and connecting rod associated with each eccentric, means arranged between one of said connecting rods and one of said rock shafts and including a rocker arm within the casing for imparting a rocking movement to said one of said rock shafts, a bell crank journalled in one of said casing parts, one of the arms of the bell crank being operatively connected to an associated connecting rod, and the other arm of the bell crank being operatively connected within the casing to the other one of the firstmentioned rock-shafts.

6. In a sewing machine, the combination of a casing having upper and lower parts, a throat plate on said lower casing part, a generally upright needle carrying bar mounted in said upper casing part for reciprocating movement toward and away from the throat plate with its axis crossing the axis of the main drive shaft, a main drive shaft journalled in said lower casing part, a bearing Wall on said lower casing part approximately parallel to said shaft, a looper rock shaft journalled in said bearing wall below the throat plate, a recess above the throat plate extending inwardly from one side of the upper casing part, an inner Wall in said recess, a loop spreader rock shaft journalled in said inner wall, said rock shafts being arranged substantially at a right angle to the main drive shaft and disposed to the same side of the plane of the needle and each having a part extending outside the associated casingr part, a looper and a loop spreader respectively each xed to one of said parts of the looper rock shaft and looprspreader rock shaft respectively extending outside of said casing parts for cooperating with the needle in forming stitches, a rocking lever in the upper part of the casing and connected to said needle carrying bar, upright eccentrics within the casing on said main drive shaft and each having a strap and a connecting rod associated therewith, there being an eccentric for each of the before mentioned rock shafts and one for said rocking lever, and means within the casing operatively connecting said connecting rods with said rock shafts and said rocking lever respectively.

EMERIC POLIMAC. 

